(We beg you).
Because it’s running a marathon Not the best way to lose weight
It’s such a common goal…wanting to lose weight, tone up, get fitter. Most of my clients have some sort of aesthetic related goal. During this initial consultation, we talk for a full hour about their goals, their current routine and what they want to change. We come up with a plan that we both feel good about as we are about to wrap up the session…
Customer: “Oh yeah, and I’m signed up for the Disney Half Marathon in 3 months!”
My inner dialogue: “NOOOOO! This will ruin everything!”
Me on the outside: “Wow, that’s such a great goal!”
I know I can’t let them down right now. I know they are so excited about the goals we set, as well as that big goal of running 13 (or even 26) miles. The idea makes sense on paper. Marathons are long, grueling, calorie-burning events. So, wouldn’t training for a fast cause you to lose weight?
Here’s the truth: marathon training and weight loss are usually competing goals. Trying to do both at the same time leads to frustration rather than success.
Not because running is bad. Is not. Running a half or full marathon is an incredible personal challenge BUT long distance running and weight loss require opposite strategies:
- Long distance running takes fuel. Your body relies heavily on fast-digesting carbohydrates (think sports gels and drinks, chews or even jellies) to perform.
- Losing weight requires a calorie deficit. This means eating less food overall, without constantly topping up sugar in the middle of time.
Trying to do both at the same time is like hitting the accelerator and the brake at the same time.
Appetite, hunger and carbohydrates
Long distance running works up your appetite. After burning through glycogen stores during a long run (over 1 hour), your body needs sugar for quick fuel. That’s why marathon runners need to eat mid-run. And what works best for fueling your run doesn’t match what you’d normally eat if you wanted to lose weight… snacks like gels, waffles, or candy. This can also make cravings afterwards feel uncontrollable.
And let’s be real: after a 15-mile workout, most people don’t want baby carrots and hummus. They want bagels, pizza and comfort food.
This is why so many distance runners don’t lose weight, despite burning huge numbers of calories. They end up eating those calories right back, many times more.
The Time Trade-off
Another reason marathons don’t pair well with weight loss? Time.
Most of our customers are busy professionals, parents or both. Training for a marathon consumes many hours each week. These are hours that could otherwise be spent on strength training, mobility, rehabilitation, meal planning or meal preparation. From a general wellness perspective, running is not the most effective way to change your body composition or improve your health.
That doesn’t mean running can’t be part of a healthy lifestyle. I personally run 3 times a week (usually just one mile, aiming for a fast pace). But if your primary goal is weight loss, spending most of your training time pounding the pavement isn’t the best return on investment.
Why running worked in your 20s
Many people look back and say, “Running worked for me when I was younger. I missed a ton of weight training for a race in college.”
Here’s why it doesn’t translate into middle age:
- Metabolic changes: Younger bodies burn more energy at rest.
- Diet history: If you’ve been dieting for decades, your body has adapted and “learned” how to conserve energy.
- hormones: A 40-year-old man starting to exercise can lose fat more easily than a 40-year-old woman approaching menopause.
Your body evolves over time. What worked at 22 rarely works the same way at 42.
Strength training vs. long distance running
Here’s the big difference:
- Strength training builds muscle, which in the long run raises your metabolism and reshapes your body. Burns calories during training and increases calorie burn afterwards.
- Running burns calories in the moment, but it doesn’t build muscle or boost metabolism in the same way.
With weights, you can train for 30–45 minutes, gain strength, and recover without needing Gatorade or gummy bears to get you through it. Craving spikes are usually shorter and easier to manage.
That’s why, for weight loss, lifting wins almost every time.
Real customer stories
A client of mine was deep into the Disney marathon scene. Running a full marathon was her life’s goal. He had already done a few halves. He also wanted to lose 50 pounds. I told her she would have to choose.
He decided to stop losing weight. She was already deep into her training and had paid to enter the race. We focused on training smart, fueling right and staying injury free. She finished the marathon, got her medal and checked that life goal off her list.
Then when we changed the focus to weight loss, she was amazed at how much easier it was. Without the constant marathon hunger, her appetite felt normal again. It took a ton of time back that was spent planning and preparing meals. He focused more on strength training and added some low-intensity, stress-relieving movements.
Don’t compare yourself to runners on Instagram
A quick reality check: many of the fit runners you see online they are not in weight loss mode. They maintain their physical condition, they are not actively trying to lose weight.
Consider athletes like Cam Hanes. He looks great for running ultramarathons, but he’s not trying to lose 20 pounds. He is already at his goal weight and training hard. His goals are not your goals.
So what is the right approach?
- If your main goal is the marathon: Fuel for performance. Eat the carbs, train hard and focus on finishing strong. Save the weight loss for later.
- If your main goal is weight loss: Prioritize strength training, moderate exercise and consistency in your diet. Running can remain, but keep your runs to 10 Ks or less.
The bottom line
Running a marathon is an amazing achievement, but it is not a weight loss strategy. For most people, it makes losing weight difficult.
If you like running, run! If you want to lose weight, focus on your food intake, strength training, and stress reduction. If you want both, choose which goal is more important to you right now, go for it, and put the other one on hold.
About the author: Megan Ware, RDN, LD, is a registered dietitian nutritionist in Orlando, Florida. He owns his private practice, Nutrition Awareness, where he teaches other entrepreneurs how to maximize their productivity and performance with nutrition. She is the author of the book The Optimized Life: A Nutrition Guide for Entrepreneurs and his co-host Nutrition Information Podcast.
If you need help losing weight, improving your performance or increasing your energy, schedule your initial consultation here.
